Recently, as a pumping source for a signal light source or optical fiber amplifier for optical communications, semiconductor laser chips have been used increasingly. When the semiconductor laser chip is used as such a light source, in many cases, it is used as a semiconductor laser diode module, a device in which a laser light emitted from the semiconductor laser chip is optically coupled to an optical fiber. Between the semiconductor laser chip and the optical fiber, a lens or optical isolator is disposed. The laser welding technique is generally applied for fixing these optical components.
The present invention provides a semiconductor laser diode module that can be used as a light source. In accordance with one aspect of the invention, a semiconductor laser diode module comprises:
a base;
a semiconductor laser chip mounted on the base;
an optical fiber for receiving light emitted from the semiconductor laser chip;
one or a plurality of optical components disposed between the semiconductor laser chip and the optical fiber; and
an optical component retaining member for retaining and fixing the optical component on the base,
wherein the bottom side of the optical component retaining member is fixed to the base and the upper side of the optical component retaining member is provided with a clamping part for clamping the optical component from outside surfaces thereof,
the clamping part is formed with a thin part on the top end side thereof, the thin part having a thickness thinner than that of the base side and having a thickness almost equal, where the optical component is laser-welded and fixed to the clamping part at a position of the top end side of the thin part having the thickness almost equal.